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--- m0dul-ethernet [2012/04/24 10:55] – sec
+++ m0dul-ethernet [2012/06/09 21:32] (current) – equinox
@@ Line 25: / Line 25: @@
   * Con: limited space means we will probably only get UDP, and maybe DHCP. Enough for our logging stuff, but difficult for other projects, only 10baseT
   * [[https://secure.reichelt.de/USB-CAN-BUS-Controller/ENC-28J60-I-SP/index.html?;ACTION=3;LA=444;GROUP=A316;GROUPID=2946;ARTICLE=89340;START=0;SORT=artnr;OFFSET=16|ENC28J60]] 2,60€ - 2,95€ bei Reichelt
+    * Please do not use this chip. It's a pain to work with, doesn't do Autonegotiation, loses packets and has weird unfixed erratas. --equinox
+  * [[http://www.micrel.com/_PDF/Ethernet/datasheets/ksz8851snl_ds.pdf|Micrel KSZ8851SNL]] [[http://de.futureelectronics.com/de/technologies/semiconductors/comm-products/switch/Seiten/3385572-KSZ8851SNL%20TR.aspx?IM=0|part source: Future Electronics]]
+    * considerably simpler buffer/queue management than the ENC28J60
+    * supports 100base-TX & Autonegotiation
+    * supports Auto-MDIX (Crossover)
+    * QFN32 package
+    * ca. 3€
 Use a "smart" Ethernet chip which has a full TCP/IP implementation.
@@ Line 38: / Line 45: @@
 Again two options here:
-"simple" homegrown POE (just use the unused pairs to send Power)
+  * "simple" homegrown POE (just use the unused pairs to send Power)
-"normal" POE (802.3af or 802.3at) (.af sounds simple - provides for ~ 200mA @ 48V - enough for us)
+    * **homegrown/uncontrolled PoE will be instantly refused by the NOC.**  Frying an 20k€ Switch by misplugging a cable is not an acceptable risk.  This applies for all uses that touch the building infrastructure -- even if it's not supposed to be linked to a "big" switch you can always misplug something.
+  * "normal" POE (802.3af or 802.3at) (.af sounds simple - provides for ~ 200mA @ 48V - enough for us)
 according to Wikipedia, the injector decides wether to provide power via the "unused" or the "data" wires, which means more work for us...
@@ Line 56: / Line 64: @@
 -> Still unclear if there are no other options.
+Discrete Magnetics:
+  * [[http://www.epcos.com/inf/30/ds/lan_mod/B78476A8245A003.pdf|Epcos B78476A8245A3]] [[http://de.futureelectronics.com/de/technologies/passives/transformers/signal-magnetic-transformers/lan/Seiten/5173968-B78476A8245A3.aspx?IM=0|source: Future Electronics]] 100MBit PoE
+Recommended reading for magnetics selection: http://www.ceetus.com.cn/paper/VSC8201.pdf (Vitesse magnetics design note, cannot find original on Vitesse's website anymore)
 ===== Connection to r0ket =====
@@ Line 63: / Line 76: @@
 ====== Software ======
 Nothing done yet. Need to decide on the Hardware first
+Please implement [[http://en.wikipedia.org/wiki/Link_Layer_Discovery_Protocol|LLDP]] and you will make the NOC happy :)
+(Possible on all of the chips, simple ethernet protocol.)
 ===== Openbeacon Reader =====